michael@0: /* -*- Mode: js2; js2-basic-offset: 2; indent-tabs-mode: nil; -*- */
michael@0: /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: "use strict";
michael@0: 
michael@0: this.EXPORTED_SYMBOLS = ["Logger"];
michael@0: const PREF_DEBUG = "toolkit.identity.debug";
michael@0: 
michael@0: const Cu = Components.utils;
michael@0: const Ci = Components.interfaces;
michael@0: const Cc = Components.classes;
michael@0: const Cr = Components.results;
michael@0: 
michael@0: Cu.import("resource://gre/modules/XPCOMUtils.jsm");
michael@0: Cu.import("resource://gre/modules/Services.jsm");
michael@0: 
michael@0: function IdentityLogger() {
michael@0:   Services.prefs.addObserver(PREF_DEBUG, this, false);
michael@0:   this._debug = Services.prefs.getBoolPref(PREF_DEBUG);
michael@0:   return this;
michael@0: }
michael@0: 
michael@0: IdentityLogger.prototype = {
michael@0:   QueryInterface: XPCOMUtils.generateQI([Ci.nsISupports, Ci.nsIObserver]),
michael@0: 
michael@0:   observe: function observe(aSubject, aTopic, aData) {
michael@0:     switch(aTopic) {
michael@0:       case "nsPref:changed":
michael@0:         this._debug = Services.prefs.getBoolPref(PREF_DEBUG);
michael@0:         break;
michael@0: 
michael@0:       case "quit-application-granted":
michael@0:         Services.prefs.removeObserver(PREF_DEBUG, this);
michael@0:         break;
michael@0: 
michael@0:       default:
michael@0:         this.log("Logger observer", "Unknown topic:", aTopic);
michael@0:         break;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   _generateLogMessage: function _generateLogMessage(aPrefix, args) {
michael@0:     // create a string representation of a list of arbitrary things
michael@0:     let strings = [];
michael@0: 
michael@0:     // XXX bug 770418 - args look like flattened array, not list of strings
michael@0: 
michael@0:     args.forEach(function(arg) {
michael@0:       if (typeof arg === 'string') {
michael@0:         strings.push(arg);
michael@0:       } else if (typeof arg === 'undefined') {
michael@0:         strings.push('undefined');
michael@0:       } else if (arg === null) {
michael@0:         strings.push('null');
michael@0:       } else {
michael@0:         try {
michael@0:           strings.push(JSON.stringify(arg, null, 2));
michael@0:         } catch(err) {
michael@0:           strings.push("<<something>>");
michael@0:         }
michael@0:       }
michael@0:     });
michael@0:     return 'Identity ' + aPrefix + ': ' + strings.join(' ');
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * log() - utility function to print a list of arbitrary things
michael@0:    *
michael@0:    * Enable with about:config pref toolkit.identity.debug
michael@0:    */
michael@0:   log: function log(aPrefix, ...args) {
michael@0:     if (!this._debug) {
michael@0:       return;
michael@0:     }
michael@0:     let output = this._generateLogMessage(aPrefix, args);
michael@0:     dump(output + "\n");
michael@0: 
michael@0:     // Additionally, make the output visible in the Error Console
michael@0:     Services.console.logStringMessage(output);
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * reportError() - report an error through component utils as well as
michael@0:    * our log function
michael@0:    */
michael@0:   reportError: function reportError(aPrefix, ...aArgs) {
michael@0:     let prefix = aPrefix + ' ERROR';
michael@0: 
michael@0:     // Report the error in the browser
michael@0:     let output = this._generateLogMessage(aPrefix, aArgs);
michael@0:     Cu.reportError(output);
michael@0:     dump("ERROR: " + output + "\n");
michael@0:     for (let frame = Components.stack.caller; frame; frame = frame.caller) {
michael@0:       dump(frame + "\n");
michael@0:     }
michael@0:   }
michael@0: 
michael@0: };
michael@0: 
michael@0: this.Logger = new IdentityLogger();